Overwinding preventer



June 3, 1952 BR1DEVAUX 2,599,161

OVERWINDING PREVENTER Filed April 17, 1951 Patented June 3, 1952 VERWENDING PREVENTER Georges Bridevaux, Tavannes, Switzerland, as signer td'Tavannes[Watch C; S.A., Tavannes, Switzerland, a firm of Svvitzrland Application April 17, 1951, Serial No.221,419

, In Switzerland December 22, 1950 6 Claims.

This invention relates to a timepiece. This timepiece is characterized by a sliding member to which the winding means imparts a reciprocating movement and on which is mounted a slider Which is capable of being displaced on the said member and carries a means for driving the barrel ratchet. this slider being returned by a coil*spring intended to yield, when the tension of the barrel spring reaches a given value, in such a way that the ratchet remains stationary even When the displacements of the sliding member continue.

The accompanying drawings illustrate, by way of exemple, one embodiment of the invention.

Figure 1 is a plan view of a timepiece;

Figure 2 is a section of a detail, on the line IIII of Figure 1; and

Figure 3 is a section on the line III-III cf Figure 1.

The timepiece illustrated is a small c1ock which is wound by means of a crank fixed to the centre of the movement. This crank, indicated by l, is shown in Figure 3; it is rigid With a hub 2 tuming on a journal 3 fixed t0 a plate 4 which carries all the winding members and is itself fixed to the bridges of the framework. The hub 2 carries a cam 5 co-operating with a pin 5 fixed to a sliding member 1, which is mounted on the plate i in such a way as to be capable of undergoing rectilinear displacements. A spring 8 tends to press the pin 6 against the cam 5. The pin 6 is situated on the axis of the member 1, which is guided by a pin 9 passing through a slot H) in the member 1 and by two screws II. A slider I2 is arranged in an elongated aperture l3 in the member 1. This slider can be displaced in this aperture; it carries a paWl 14 which a spring l5 presses against a ratchet l6 which f0rms part of the winding system. The pawl I4 is displaced tangentially to the ratchet Hi, so that no force is wasted. The ratchet [5 is rigid With a pinion l1 driving the wheel l8 of a moving member, of which the pinion i meshes with the barrel ratchet indicated by 26. A11 these moving mem bers, With the exception of the barrel ratchet, are carried by the plate 4. The pinion 19 is situated underneath the barre] bridge 2l. The pawl [4 is pivoted about a screw 22 engaged in the slider i2 and keeping this slider pressed against a fiange 13a of the aperture l3. The sliding member 1 also carries a lever 24 pivoted at 23 by one of its extremities, while to its other extremity is fixed 3. pin 25 for the attachment of a. coil spring 26. The other and of this spring is attached to a corner-piece 21 fixed to the sliding member 1 2 by a screw 28. This corner-piece 21 can bezdlsplaced on the member l, whereby adjustment of the tension of the spring 26 is rendered possible. The lever 24, subjected to the action of thecoil spring, acts on an abutment l2a of thesliderl2 so as to keep this slider pressed against une extremity of the elongated aperture 13. The axis of the spring 26 is parallel to the direction of the displacements of the slider l, so that the Whole of its strength is used without any loss inlateral components.

When the crank lis actuated, the cam 5 acting on the pin 6 displaces the 'sliding member l against the spring B. A reciprocating movement is then imparted to the member i, independently of the direction of rotation of the cam 5. While the slider l2 remains in the position shown in Figures 1 and 3, the pawl l4 causes the ratchet l6 to turn in the direction of the arrow 29. As soon as the tension of the barrel spring reaches a given value, if the winding force is greater than the tension of the spring 26 the pawl l4 impinges against the ratchet Hi and the slider l2 is immobilised, the spring 26 yielding when the displacement of the member 1 continues. The slider l2 is then displaced, in the elongated aperture 13, in relation to the member 1. By adjusting the tension of the coil spring 26 it is possible to adjust the maximum tension to which the barrel spring is to be wound.

In the exemple illustrated the cam is actuated by the crank I situated on the outside of the case of the small clock, the back of which is indicated by 30 (Figure 3), but this invention may equally wel1 be applied to watches with automatic winding, in which event the hub 2 could carry an oscillatin winding mass situated inside the case.

What I claim is:

1. In a timepieee, a barrel spring, a barrel ratchet, a sliding member, a pin rigid With said member, a rotary cam, a spring acting on said pin to keep it in contact with said cam so that said cam imparts to said sliding member a reciprocating movement, a slider mounted on said sliding member and capable of being displaced on said member, a means carried by said slider for driving said barrel ratchet, and a coil spring returning said slider and intended to yield, when the tension on the barrel spring reaches a given value, in such a way that the ratchet remains immobile even When the displacements of the sliding member continue.

2. In a timepiece, a winding means, a barre] springn a barre1 ratchet. a sliding member to which said windmg means imparts a reciprocating movement, a slider mounted on said sliding member and capable of being displaced on said member, a means carried by said slider for driving said barrel ratchet, a lever pivotecl by one of its extremities on said sliding member, and a coi] spring attached on the one hand to the other extremity of said lever and on the other hand to said sliding member, said lever bearing against said slider so as to return it to a given position in relation to said sliding member, said coil spring being intended to yield, when the tension on the barrel spring reaches a given value, in such a way that the ratchet remains immobile even when the displacement5 of the sliding member continue.

3. In a timepiece, a winding means, a barrel spring, a bar1el ratchet, a sliding member to which said winding means imparts a reciprocating movement, a slider mounted on said sliding member and capable of being displaced on said member, a means carried by said slider for driving said barrel ratchet, a lever pivoted by one of its extremities on said sliding member, a coil spring attached on the one hand to the other extremity of said lever and on the other hand to said sliding member, said coil spring having its axis parallel to the direction of the displacements of said slider and a device enabling the tension of said coil spring to be adjusted, said lever bearing against said slider so as to return it to a given position in relation to said sliding member, said coil being intended to yield, when the tension on the barrel spring reaches a given value, in such a way that the ratchet remains immobile even when the displacements of the sliding member continue.

4. Timepiece as claimed in claim 1, in which the displacements of the sliding member are producecl by the rotation of the cam in either direction.

5. In a timepiece as claimed in claim 1, a case, a crank situated on the outside of said case and driving said cam.

6. In a timepiece, a Windlng means, a barrel spring, a barrel ratchet, a sliding member to which said wincling means imparts a reciprocating movement, a slider mounced on said sliding member and capable of bein clisplaced on said member, a means carried by said slider for driving saicl barrel ratchet, and a coi] spring returning said slider and intended to yield, when the tension on the barrel spring reaches a given value, in such a way that the ratchet remains immobile even when the displacements of the sliding member continue, said slider being mounted in an elongated aperture made in said sliding member.

GEORGES BRIDEVAK.

RFRENCES CETED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,789,043 Jacot Jan. 13. 1931 

